Check that tube or cave

Adult Altolamprolgus calvus rescued from a rock filled bucket. Photo by the author.

As part of my regular maintenance, I remove all rocks and caves in each half of every tank once every month. I do this to all of my tanks. I change water and vacuum my sand weekly. I remove the rocks and caves so I can get any detritus that accumulates underneath them…and believe me, it does.

As part of this maintenance routine, I place all the components that I remove into a bucket. Because I have some rectangular, ceramic tubes with one end closed, I have to remove them open side down inside the tank so the water drains out. I also have to check them because my fish will seek refuge in them, especially when I’m cleaning.

This morning I removed half of the rocks and caves from one of the 75g tanks. This tank contains three adult Altolamprologus calvus. If your calvus are like mine, they will wedge themselves into some very tight spaces when they get spooked. Because of this, I usually check my tubes and caves pretty closely before I put them into a 5 gallon bucket. I’m sure by now you can see where I’m going with this.

Yes, I was in the middle of vacuuming when I heard something move nearby. Because I have lots of rocks and caves, and these will often shift or settle once in the bucket, hearing a noise come from the bucket is normal.

Call it a fish keepers well trained ear, but something about the sound I heard wasn’t right. It wasn’t a continuous “flopping” sound, as you would expect from a stranded fish. It was a single noise but it wasn’t the normal, settling sound of rocks shifting. So I look into the bucket and down between some rocks is one of my calvus! It had been in the bucket, without water, for probably close to 5 minutes. Also, because my calvus are jet black in color (and my bucket is a dark blue), it wasn’t easy to seem him but I could see slight movement. Needless to say, I quickly removed some rocks so I could get to him, scooped him up with one hand, and quickly got him back into the tank.

Nine hours later, he’s no worse for the wear except for a split caudal fin (see photo at the top). If you’re familiar with calvus and Altolamprologus compressiceps, they have thick, overlapping scales on their flanks that serve as protection for when they squeeze through tight crevices in the wild. Those scales also offer protection from predators and conspecifics. When attacked, these cichlids will expose their flank to the aggressor, allowing the thick scales to absorb the contact. The photo below illustrates this behavior perfectly. These are two of my calvus when they were juveniles.

A. calvus (juveniles). Note the defending calvus bending its body to expose its flank, which is heavily protected by scales. Photo by the author.